Hello!
On 29 Oct 2020 at 10:10, david larsson
<[email protected]> wrote:
On 2020-10-28 13:49, Sébastien Lerique wrote:
[snip]
While running a racket program which uses OpenCV, I realised
that my
LD_LIBRARY_PATH does not contain my user's profile libs. I have
`libopencv*.so` in `~/.guix-profile/lib/`, but running a racket
program which needs that fails:
```
$ racket capture.rkt
ffi-lib: couldn't open "libopencv_core.so" (libopencv_core.so:
cannot
open shared object file: No such file or directory)
```
While running
```
env LD_LIBRARY_PATH=/home/sl/.guix-profile/lib/ racket
capture.rkt
```
works.
(Also, this <http://0x0.st/ik3s.txt> is the output of `env
LD_DEBUG=libs racket capture.rkt`.)
Is this normal behaviour, i.e. that the path to dynamic libs
installed
in my user profile should be manually configured in my shell
startup
scripts? Should this not be included in
`~/.guix-profile/etc/profile`?
I wondered the same, and got answer in the IRC #guix that
setting
LD_LIBRARY_PATH is highly discouraged (unless you have a
specific and
good reason to do so in a specific case - never globally). I a
good explanation
about it here:
https://web.archive.org/web/20060719201954/http://www.visi.com/~barr/ldpath.html
A good example of how it can go wrong:
"In its startup script[a program called WidgetMan], it sets
LD_LIBRARY_PATH to
point to its copy of Motif so it uses that one when it runs. As
it happens,
WidgetMan is designed to launch other programs too.
Unfortunately, when
WidgetMan launches other apps, they inherit the LD_LIBRARY_PATH
setting and some
Motif based apps now break when run from WidgetMan because
WidgetMan's Motif is
incompatible with (but the same library version as) the system
Motif library.
Bummer!"
Yes I see that makes sense. Does this mean that one shouldn't
install libraries in user profiles?
Or maybe that, if I were to package this racket program, then it
would depend on `opencv` and set its required lib paths properly
in its package definition (so work no matter if it's system-wide
or in a user profile)?
Then, for development, is setting LD_LIBRARY_PATH still the only
way without installing the lib system-wide?
(that's a lot of questions, apologies!)
